[Global Media Controls] Add GlobalMediaKeysListenerWin implementation

This CL adds a Windows implementation of a global MediaKeysListener.
This implementation uses a KeyboardHook to receive media key events.

Bug: 902379
Change-Id: Ieb4003292e2a0622e500b83c1d8b298129e1f1fe
Reviewed-on: https://chromium-review.googlesource.com/c/1362197
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Joe Downing <joedow@chromium.org>
Commit-Queue: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615685}
9 files changed